title: Calcified tissue formation of subcutaneously transplanted mouse dental pulp.
abstract: It is well established that dental pulp has the ability to form calcified tissue, however, the precise process of calcified tissue formation and its characteristics are still undetermined. In this study we examined the process and the matrix components of the calcified tissues by means of subcutaneously transplanted dental pulp tissue. The mid-third of the mouse incisor pulp was transplanted into abdominal subcutaneous tissue. Two calcified tissues were independently formed within the implanted pulp at 7 days after the implantation, one developed in the peripheral region and the other was formed in the middle region of the pulp. Histological investigation indicated the existence of hypertrophic chondrocytes in the peripheral calcified tissue. Immunohistochemical study indicated the colocalization of types I and II collagen surrounding these cells. RT-PCR analysis indicated the transient expression of type II collagen at 7 days and the constant expression of type I collagen, osteonectin, osteocalcin and dentin matrix protein-1 and 2 at all examined times. Dentin sialophosphoprotein was only detected at 28 days after the transplantation. These results indicated that dental pulp cells might have the capacity to form calcified tissue by implanted dental pulp and it is possible that the difference of local environments induced the cells to form different types of calcified tissues within the implanted pulp.
authors.affiliation: Department of Oral Anatomy and Developmental Biology, Showa University School of Dentistry, Shinagawa-ku, Tokyo, Japan.
authors.forename: Mariko
authors.initials: M
authors.lastname: Ikeda-Isogai
authors.forename: Tadanobu
authors.initials: T
authors.lastname: Ohtsuka
authors.forename: Kazuyoshi
authors.initials: K
authors.lastname: Baba
authors.forename: Naoko
authors.initials: N
authors.lastname: Nonaka
authors.forename: Masanori
authors.initials: M
authors.lastname: Nakamura
mesh_terms: D000818:Animals; D024042:Collagen Type I / Q000032:analysis / Q000235:genetics; D024043:Collagen Type II / Q000032:analysis / Q000235:genetics; D003782:Dental Pulp / Q000473:pathology* / Q000637:transplantation*; D003784:Dental Pulp Calcification; D016326:Extracellular Matrix Proteins / Q000032:analysis / Q000235:genetics; D007150:Immunohistochemistry; D051379:Mice; D008813:Mice, Inbred ICR; D015675:Osteocalcin / Q000235:genetics; D015676:Osteonectin / Q000235:genetics; D010750:Phosphoproteins / Q000032:analysis / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012795:Sialoglycoproteins / Q000032:analysis; D040521:Subcutaneous Tissue; D000099311:Dentin Sialophosphoprotein
chemical_list: D024042:Collagen Type I; D024043:Collagen Type II; D016326:Extracellular Matrix Proteins; D015675:Osteocalcin; D015676:Osteonectin; D010750:Phosphoproteins; D012795:Sialoglycoproteins; D000099311:Dentin Sialophosphoprotein; C513308:Dmp1 protein, mouse; C407548:dentin matrix protein 2